Method of treating silver ores



L. P. BURROWS.

METHOD OF TREATING SILVER ORES. APPLICATION FILED DEC. 5, 1916. REHEIWED NOV. 99.

1,355,795. 4 Patented Oct. 12, 1920.

A .\y/ /777'J LINUS PORTIER BURROWS, OF OTTAWA, ONTARIO, CANADA.

METHOD OF TREATING SILVER ORES.

Application filed December 5,"1 916 Serial No; 135323.

To all whom it may concern: p

Be it known that I, LINUS PORTIER BUR- ROWS, a citizen of the United States, andresiding at 380 McLeod street, in the c ty of Ottawa, Province of Ontario, Domnion of Canada, professor, have invented certan I new and useful Improvements in lvlethods of Treating Silver Ores, of which the following is a specification.

This is a discovery and relates to the recovery of silver and other metals from silver ore and its result is the obtainment of a maximum amount of the metals in purified form in a. minimum of time'as well as rendering commercially practicable the treatment of ores of such low grade as has heretofore been impossible. u

The discovery consists in a method of treating the ore directly with the gas described in my Patent No. 680,313, n any suitable apparatus such as the one shown in the accompanying drawings whch show a sectional elevation of the apparatus.

The apparatus comprises an expanson, a radiatio n and precipitation chamber A, a digester-B and a plurality of precipitating chambers C, only one of which is shown. The digester B includes a treating chamber E, in which the materia-l is treated. For convenience in agitating the material the treating chamber is constructed in the form of a rotatable drum having hollow side trunnions 10 and 11 Secured to the ends 12 and 13 of the drum.

Suitable means are provided for heating the material in the drum. In the embodiment illustrated I have surrounded the treating chamber with afurnace or heating chamber F constructed with a suitable sheet metal shell 14 lined with firebrick, or other heat resisting material 15. The heating may be accomplished by any 'Well known means such as a gas burner 16 supplied with a gas supply pipe 17. V

The air for combustion of the gas may pass in through the opening 18, and the products of combustion flow out through the opening 19.

The turning of the treating chamber is accomplished by convenient means, such as the gear 20 mounted on the trunnions 11 and driven from the pinion 21 on the coun-,

tershaft 22, which counter shaft is supported by suitable bearings23 and 24 and driven Specification'of Letters Patent.

Pateted Oct. 12, 1920. Renew-ed November l, 1919. Serial No. 335,]08.

from a pulley 25. The trunnions 10 and 11 are supported by bearings 26 and 27.

The expansion, radiation and precipitaton chamber A is in the form of a cylindrical metallic container of metal preferably sheet iron, in which the steam is adapted to suddenly expand from substantially the center of the container, being introduced from the center by a pipe 40 which extends throu h the side of the chamber. On the top of the chamber is a dome 41 from which the crude gas or gases pass into a delivery pipe 42.

A weighted pop valve 43 leads from the pipe 8 into the atmosphere and serves to maintain a substantially uniform pressure in the said pipe. The pipe 42" also contains a control valve 44.

The water of preciptation is removed by a suitable valved outlet l?) at the bottom of the chamber controlled by a ball fioat 46 which causes the water to flow off as 'soon as it rises to any considerable height in the bottom of the chamber. A ma nhole 47 may be provided normally closed by a door 48.

The steam produced froni water which forms the base of the gaseous product may be produced in any convenient way. After the process is started it may be produced by the heat radiating from the furnace F, and accordingly a heating coil H is shown embedded in the walls of the 'u'nace supplied by a pipe 51 leading from a suitable source of -water supply.

From the coil H a pipe 52 leadsto the chamber A. From the chamber A the resultant gaseous product passes by the pipe 42 and a pipe 53 to suitable coils I in the chamber F,'whereby the gas is heated to a high temperature. From the heating coils I, the resultant gaseous product passes by the pipe 54 to the valved injecting nozzle 55 which projects through the hollow trunnion 10 having a gas tight joint therewith. The

gaseous product is discharged through the nozzle F into the chamber E to act upon the substances therein. A suitable pressure gage 56 may be provided to indicate the pressure at this point and the flow may be controlled by a suitable valve 57.

The gaseous products of the reaction in the chamber E passes 'through the hollow Conduit 60 leading to the side of the first precipitating chamber C. A pluralty of similar precipitation chambers will beprovided connected in series. e

The above description of the making of the gas forms no part of this invention as it is only a reiteration of the method disclosed in my Patent No. 680,313.

In practically carrying out the process a suitable quantty of silver ore, such as cobalt silver ore usually an arsenide or sul-,

fid of silver with varying quantities of cobalt nickel, is ground to mesh and placed in the chamber E, whichis then continuously ,rotated and heated to red heat during the operation of the process.

The g "eous reagent made in accordance with Pa ent 680313 is continuously injected into the ore rotating in the chamber E until the refinin is carred to the desired point, .the time w ich this occupies for a given ore being ascertained by test but is only a matter of hours. y

The material in the container F is then removed and smelted in a crucible furnace or any other convenient way to separate the metal from the gangue or silicious material, a fiux may be used if necessary to facilitate the smelting.

After cooling the crucible, its contents are dumped out and found to be in the form of superposed distinct layers or cakes, silver being on the top of the pile, then the other metals of the ore such as cobalt, nickel, etc., and then the slag which takes a decidedly crystalline form. I

n carrying out the process in connection with ores having an acid character it may be found desirable to add counteracting substances such as sodium chlorid or potassium chlorid, the same being inserted in the chamber E.

a' Asmany changes could be made in the above invention and' many' apparently or scope thereof, it is intended that all matter contained in the' accompanying specifica- 'tion and drawings shall-be nterpreted as illustrative and not in a limiting sense. I claim-- I i 1. A method of the class described con-.

sisting in first suddenly expanding steam,

then separating the steam without condensation ore to the gaseous product at red heat', smelting the treated ore, and cooling the result whereupon the diflerent metals contained in the ore are found to bein purified condition and in separate layers.

` rom any water held in suspension, then heating the gaseous product to a high temperature, and subiecting crushed silver 2. The method of claim 1 in whih a chlorid of an alkaline earth metal is added to the ore before treatment with the gas. 3. The heren described process consisting in first suddenly. expanding steam, then separating the steam from any water held in suspension, then heating the gaseous product to a high temperature and subjectingcrushed silver ore containing a metal of the iron group to the action of said gaseous product'in a closed cylinder `at a red heat and thereafter subjecting said treated and refined ore to a smelting process, the re-` sultant product being stratified into magnetic and non-magnetic metal whenlcold, the resultant silver product being of from 800 to 900 fine. V

In witness whereof I have hereunto set my hand.

LINUS PORTER BURROWS. 

